Actuator apparatus utilizing a shape-memory alloy

Abstract

An actuator apparatus includes a plurality of actuators each having a shape-memory alloy, a power supply line unit for supplying power to the actuators, power supply control unit connected in series with at least one of the actuators, and a driving unit for driving the power supply control unit.

What is claimed is: 
     
       1. An actuator apparatus comprising: a plurality of actuators each comprising a shape-memory alloy;   power supply line means for supplying power to said actuators;   power supply control means connected in series with at least one of said actuators; and   driving means for driving said power supply control means.   
     
     
       2. The apparatus according to claim 1, wherein said power supply control means includes a semiconductor switch. 
     
     
       3. The apparatus according to claim 2, wherein said semiconductor switch includes a MOS field effect transistor. 
     
     
       4. The apparatus according to claim 2, wherein said semiconductor switch includes a phototransistor. 
     
     
       5. The apparatus according to claim 4, wherein said driving means includes an optical fiber for guiding light to said phototransistor, and a light source and an optical filter for supplying light to said optical fiber. 
     
     
       6. The apparatus according to claim 1, further comprising: a holding member for holding said actuators; and   disabling means for disabling an operation of said actuators when said actuators are overheated.   
     
     
       7. The apparatus according to claim 6, wherein said disabling means for disabling an operation of said actuators includes separating means for separating said actuators from said holding member. 
     
     
       8. The apparatus according to claim 7, wherein said actuator separating means includes a small-diameter portion formed at an end portion of said shape-memory alloy. 
     
     
       9. The apparatus according to claim 7, wherein said actuator separating means includes a heat-melting member located at an end portion of said shape-memory alloy. 
     
     
       10. The apparatus according to claim 7, wherein said actuator separating means includes a heat-shrinkable member located at an end portion of said shape-memory alloy. 
     
     
       11. The apparatus according to claim 1, wherein: said power supply line means includes a pair of power supply lines; and   said plurality of actuators are connected in parallel to said power supply lines; and   said plurality of actuators are connected in parallel to said supply lines.   
     
     
       12. The apparatus according to claim 11, wherein: said power supply control means includes semiconductor switches; and   each semiconductor switch is connected in series with each actuator.   
     
     
       13. The apparatus according to claim 12, wherein said actuators are arranged in an insertion section of an endoscope. 
     
     
       14. The apparatus according to claim 13, wherein said semiconductor switches are arranged in the insertion section of the endoscope. 
     
     
       15. An actuator apparatus comprising: a plurality of actuators each comprising a shape-memory alloy;   power supply line means for supplying power to said actuators;   power supply control means connected in series with at least one of said actuators; and   driving means for driving said power supply control means;   said power supply line means including a pair of power supply lines, and said plurality of actuators being connected in parallel to said power supply lines.   
     
     
       16. The apparatus according to claim 15, wherein said power supply control means includes switch means connected in series with each of said actuators. 
     
     
       17. The apparatus according to claim 16, wherein said actuators are arranged in an insertion section of an endoscope. 
     
     
       18. The apparatus according to claim 17, wherein at least one of said power supply lines extends into the insertion section of the endoscope. 
     
     
       19. The apparatus according to claim 18, wherein said switch means is arranged in the insertion section of the endoscope. 
     
     
       20. The apparatus according to claim 19, wherein said switch means includes a semiconductor switch. 
     
     
       21. An actuator apparatus comprising: a plurality of actuators each comprising a shape-memory alloy;   power supply line means for supplying power to said actuators;   power supply control means connected in series with at least one of said actuators; and   driving means for driving said power supply control means;   said actuators and said power supply control means being arranged in an insertion section of an endoscope.   
     
     
       22. The apparatus according to claim 21, wherein: said power supply line means includes a pair of power supply lines; and   said plurality of actuators are connected in parallel to said power supply lines.   
     
     
       23. The apparatus according to claim 22, wherein at least one of said power supply lines extends into the insertion section of the endoscope. 
     
     
       24. The apparatus according to claim 23, wherein said power supply control means includes switch means connected in series with each of said actuators. 
     
     
       25. The apparatus according to claim 24, wherein said switch means includes a semiconductor switch.